As an outdoor display device, an LED module is generally mounted on a wall or a frame in a plate form to broadcast advertisements or other image. In order to adapt to different mounting environments, and to obtain better visual effect, people often set the LED modules in curved surface forms. For example, Chinese patent CN202549189U discloses an S-shaped LED module, by connecting LED modules on both sides together through a flexible connecting board set on a curved part, the LED module of the patent document can be mounted on a wall with corner. Such an S-shaped LED module may have the following defects: 1. at the corner of the S shape, an U-shaped or V-shaped connecting plate is used to connect the LED modules, the LED module itself can't bend, and is not suitable to close and fit curved walls; the connecting plate can't be used to display images, such that displayed images will be cut off; 2. in assembly, the LED modules on both sides need to be connected with the connecting plate by riveting or welding, therefore mounting is relatively cumbersome and difficult.
In order to solve the technical problem that the S-shaped LED module are not applicable to close the curved walls, the displayed images are cut off, and mounting is difficult, China Patent CN104008707A discloses a arc-fixing rod for a bendable LED display screen, which comprises a flexible screen unit comprising a plurality of LED lamp strips arranged transversely. Two arc-fixing rods are arranged on the top and the bottom of the back of the lamp strip, two mounting bases of each arc-fixing rod are respectively fixed with the LED lamp strips on both sides. Each arc-fixing rod comprises a telescopic rod and the two mounting seats. Two ends of the telescopic rod are respectively hinged with the two mounting seats. The telescopic rod comprises a sliding rod, a sleeve and a locking mechanism. The sliding rod is inserted into the inner hole of the sleeve, and is matched with the inner hole of the sleeve, and the sliding rod is axially fixed by the locking mechanism. But the arc-fixing rod of the bendable LED display may have the following disadvantages: 1. the LED display screen is formed by a plurality of LED lamp strips arranged transversely, a gap is formed between every two LED lamp strips, such gaps will expand when the LED lamp strips are bent into an inner arc, which makes the display effect be worse; 2. the telescopic rod has a tube-in-tube structure, the locking mechanism includes a rotary head and a handle, the telescopic rod is locked in a transverse groove through the handle of the locking mechanism, the angles of the curved display screen are not continuous, the curve of the display screen is a discontinuous curve determined by the number of the transverse grooves and the gaps between the transverse grooves, which makes the applicability be low; 3. the locking mechanism, telescopic rod and column have relatively complex structures, great weights, and high production cost.